/*
 * C/C++ Lessons Program
 * 
 * Copyright (c) 2012 Ken Zhang (cpp.china@gmail.com)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA  02111-1307  USA
 *
 */


#include <setjmp.h>
#include <stdio.h>
#include <string.h>

char *strtrim(char *str)
{
	int i, n;
	const char *charlist = " \t\r\n";
	
	n = strlen(str);
	if (n > 0) {
		for (i = n - 1; i >= 0; i--) {
			if (strchr(charlist, str[i]) != NULL)
				str[i] = '\0';
			else
				break;
		}
		
		for (i = 0; i < n; i++) {
			if (strchr(charlist, str[i]) == NULL) {
				return str + i;
			}
		}
	}
	
	return str;
}

void try_block(jmp_buf *env)
{
	char buffer[128], *line;

	printf("Please input commands, 'quit' to exit.\n");
	printf("  or 'throw [1|2]' to throw exceptions.\n");

	do {
		line = fgets(buffer, sizeof(buffer), stdin);

		if (line != NULL) {
			line = strtrim(line);
		}

		if (!strcmp(line, "throw 1")) {
			longjmp(*env, 1);
		}
		else if (!strcmp(line, "throw 2")) {
			longjmp(*env, 2);
		}
		else if (!strcmp(line, "throw")) {
			longjmp(*env, 9);
		}
		else {
			printf("  Your input is: '%s'\n", line);
		}
	} while (strcmp(line, "quit"));
}

void catch_exception1()
{
	printf("Exception Type 1 is caught.\n");
}

void catch_exception2()
{
	printf("Exception Type 2 is caught.\n");
}

void catch_other_exceptions()
{
	printf("Exception (any other type) is caught.\n");
}

int main()
{
	jmp_buf jbuf;

	switch (setjmp(jbuf)) {
	case 0:
		try_block(&jbuf);
		break;
	case 1:
		catch_exception1();
		break;
	case 2:
		catch_exception2();
		break;
	default:
		catch_other_exceptions();
		break;
	}
}

